Apparatus for photochemical reactions



Allg- 19, 1958 H. G. BoYNToN ETAL 2,848,623

APPARATUS Foa PHoTocHEMIcAL REACTIONS Filed Oct. 20. 1955 2 Sheets-Sheet 1 FIG.

n rana on nso/v l l l Fein I E 47 g FIG. 5. 48 INVENToRs. 53% n; Harry G. Boynton, s L, 35 g 58 Evere/f W. Lewis, 0' a2 02 "Y ""SIMYV L Albert T. Watson,

5oJ 52 A ug- 19, 1958 H. G. BoYNToN ErAL 2,848,623

APPARATUS FOR PHOTOCHEMICAL REACTIONS Filed Oct. 20, 1955 2 Sheets-Sheet 2 u www, d umn LAMPS m WMM FIG. 4.

0/L FEED INVENTORS. Harry 6. Boynton, Everett W. Lewis, A/oorf 7'. Watson,

"atent 2,848,623 Patentedu'g; 19, 1958 f.. ICC

11 Claims. (Cl..250-47) Tliepresent, inventions:directed to a method for reacting ch'emicalsphotochemically; More speciiically, the' invention is directed to a method for conducting' photo chemical'reactions. at high pressures. In itsmore` specific aspects, the invention is. concerned with a methodfor reacting hydrocarbons at high pressures in a novelre.- action'zone'.

The present-invention may be briey described as a reactor vessel: for photochemicall reactions which comprises a vessel' adapted to contain a liquid body of a vaporizable refrigeranta'nd provided with means for introducing' vaporizable' refrigerant to and withdrawing vaporizable refrigerant from said vessel; Arranged in saidfvesselxare: a pluralityof photochemicallamps. A glass "reaction coil or one suitably made of material transparent to liglit` is` arranged"` in` the vesselin proximityto the lamps to describe a path through said vessel. TheV vesselv is providedin its upper part with means for condensing refrigerant. Means: are'provided' for 'introducing reactants-intothesaidcoir and means arev provided for' withdrawingl product' from said coil.

The invention also includes a' method for reacting hydrocarbons' andl the-like under high pressures wherein a' mixture, fory example, of sulfur dioxide andhydroc'arbonsis reactedz in a glass' reactionzone` under higlipres# sures. Thelglassreaction`l zone ismmersed in a liquid pool of avaporiZ-'ab1e,normally gaseous hydrocarbon and the mixture' is then exposed in said immersed reaction zone 'to' radiations of a'sutiicient`- wave length at a` selected pressure at least as great as' the safe-working pressureof thereaction: zone. Thevv pool is maintained during'ex'- posureinfthe vapori'zablehydrocarbonwliich has" a vapor pressure correspondingtolthel selected pressure.

The'photochemical lampsemployed inl the practice of' the presentl invention may suitably bemercuryl vapor' lamps andY mayf be' lamps such as'` described in the`patent to Roberts `et al. U: S: 2,5283320issued October 31, 1950; Other photochemica-l lampsg-such as well known in'Y the art, maybe employed. Lamps such as described in the patent to Henke et a1. U.. Se 333,568 issuedNovember 2, 1943, may also'befused.. These lampsfprovide radiationt of a suitable wave'lengthfin the range from 3000l to 5 800 A.

The refrigerantV or the vaporizable, normally gaseousk hydrocarbon may bey ethaneypropane, butane, and? the like, aswell as other vaporizable refrigerants such" as those of the Freon type- Other refrigerants whchlwill meet the characteristics of being transparent to radiation' of thewave length required: for initiating photochemical reactions, volatilizable and readily liqueable may` suitably be used.v Y

The reactionV conditionsv employed in the practiceof the present' invention may encompasstemperatures in the range from about to-about-300 F. Temperatures'of about l'S" F. may give satisfactory results. Pressur'esy suitably may range from about 25'poundsupto about'- vided a bank of lamps oralpluralityv of banks of` lamps of the type mentioned'supra. A glass coil reaction tube'f is arranged to describe a tortuous path through the-vessel and the reactionV coil is provided with an inlet for introducing reactants and' an outlet for recovering' product therefrom.

The upper portion. of the reaction vessel, which may be in the form of a vapor dome, isfsuitablyv provided with or has connected thereto acondensing means for conf' densi'ng the' refrigerant which removes heat" of'v reaction by vaporization of the refrigerant.

The hydrocarbons employedasreactants in thefprese'nt invention may suitably be paralinic' andn'aphthenic hyi drocarbons as exemplified by hexane, heptane, octane, nonane, and the higher members" of the same homologous series'.

used. Lubricating oils produced by solvent extraction of lubricating oil fractions are entirely suitable as feed stocks; i

The naphthenic hydrocarbons, such as the single`- ring naphthenes, suchl as cyclohexane and the higher inembers of the same homologousy series' mayl alsol be used.

Mixtures of naphthenic and parafnic hydrocarbons mayv The invention will be further illustrated by reference' to 'the drawing i in which:

Fig. l is a sectional'view of one embodiment;

Fig; 2 is aview'taken along the lines I'-I- of Fig. l;

Fig. 3 is a modification ofthe embodiment of Fig. l; and

Fig. 4 is a view of a preferred embodiment.

Referring'now to the'drawing andfpja'rticul'ar-ly Figs. 1 and 2 in which' identical numerals will be employed to designate identical parts, numeral 1:1 designates a horizontal, elongated reactionvessel suitably'comprised of asteel shell which may be provided with an internal reecting surface'12 which'maybecomposedlof a reilecting metal, such as stainless steel' or aluminum, silver and thev v like.

The upper portion ofthe vessel 11 isinthe form of a vapor dome 13 having a condensing coil I4y arranged therein through which water or other cooling medium may be circulated therethrough by inlet line 15y and outlet line- 16.

The vessely 11 is provided with abank 1'7 coinposed'ofy a plurality of photochemical lamps 18o'f the type mentioned supra. These lamps are spaced apart from each other' andA from the internal walls of! the vessel 11'. Arranged' to describe a tortuous path through the bank 17 isa glass reaction coil 19, as shown more clearly in Fig. l, into which reactants, such as hydrocarbons, may be introduced by way of line 20, sulfur dioxide by Way of' line 21 and chlorine by way of line 22; Line 20 is providedl with mixing devices 23 and 221 which suitably may be bailleplate incorporators although other mixing devices, such as centrifugal pumps, mixing towers havingl internal vapor-liquid contacting means and the like may be used.

The glass coil- 19 is provided withv an outletline 25 by way of which the photochemicalv reaction product, such as hydrocarbon'sulfonyl chlorides, may be removed; The lamps18 and bank 1`7 are suitably connected by electrical connecting means 26 to ballasts, starters, and voltage source, not shown, which are well known in the art.

It is to be noted that the vessel 11 is provided with' manholes 27 and 28 for easy access thereto and the' vapor domeV 13is also provided with a manhole 29'f'or ready access, the several manholes 27, 28 and 29`bein'g suitably closed by bolted flanges.

Hydrocarbons boiling in the naphtha, kerosene,- gasoil and lubricating oilboiling range may also` bev Referring now to Fig. 3, a vertical, elongated reactor 30 is provided with a plurality of longitudinally extending lamps 31 of the type mentioned. Arranged to provide a flow path in proximity to the lamps is a reaction coil 32 of light transparent material'into which oil and sulfur dioxide are introduced by way of line 33 and chlorine by line 34.

The products from the coil 32 are discharged therefrom by line 35 for further processing of the hydrocarbon sulfonyl chloride.

The reactor vessel 30 is closed on the upper and lower ends by bolted anged heads 36 and 37.

Arranged in the vessel 30 is a body 38 of liquid refrigerant, such as liquefied butane and the like, which is arranged to cover the lamps 31 and the coils 32. Arranged in the vapor space 39 above the body 38 is a condensing means, such as a coil 40, through which water is circulated by Way of lines 41 and 42.

The vessel 30 is provided with line 43 controlled by valve 44 for introduction of makeup refrigerant and with line 45 controlled by valve 46 for withdrawing the refrigerant.

The vessel 30 is provided with a steam chest 47 having a steam coil 48 arranged therein into which steam is introduced by line 49 and withdrawn by way of line 50 and steam trap 51 and discharged by line 52. Steam chest 47 allows regulation of temperature in the reaction zone.

The liquid level of refrigerant in vessel 30 may be indicated by a gauge glass 53 connected to the vessel 30 by lines 54 and 55.

Connected to line 54 and to vessel 30 by line 56 is a pressure recorder controller 57 which, in turn, connects to a valve 58 in line 49. This pressure recorder controller 57 serves to introduce and cut off steam into the coil 48 for maintenance of temperature in the vessel 30.

A vent line 59 controlled by valve 60 allows vapors to be vented from the space 39. Electrical leads 61 are carried through an electrically insulated bushing 62 through the wall of vessel 30 and connected to an electrical system, not shown.

Referring to Fig. 4, which is a modilcation of Fig. 3 and is a preferred embodiment, numeral 70 designates an elongated, vertical reaction vessel in accordance with the present invention having a plurality of longitudinally extending lamps 71 arranged therein at spaced apart intervals at a plurality of levels. Conveniently, 24 lamps may be arranged in banks at four levels in the vessel. These lamps may be centered equally on a 2 inch diameter circle and supported by a suitable frame member 72.

A light transparent coil, such as glass coil 73, is arranged around the lamps 71. The oil feed may be introduced by line 74, sulfur dioxide by line 75 and chlorine by line 76 into coil 73. Product is withdrawn from coil 73 by line 73a comprising hydrocarbon sulfonyl chloride. controlled by valve 78 and is provided with a gauge glass 79 connected to the vessel 70 by lines 80 and 81.

Connected to the upper -end of the vessel 70 by line 82 is a condensing means 83 through which water is circulated by line 84, controlled by valve 85, through coil 86 and withdrawn by line 87. The condensed refrigerant is returned to vessel 70 by line 90 controlled by valve 91. The valve 85 in line 84 is connected to the upper end of the vessel 70 by line 92 through a diaphragm arrangement 93 which serves to control the valve 85 to regulate the flow of water through line 84. Electrical leads 94 connect to the lamps 71 and are carried to the exterior of the vessel through an electrically insulated bushing 95 to connect to an electrical power source, notv ;hown.

The vessel 70 may be designed to operate at a temaerature of about 200 F. and a pressure of 100 pounds per square inch gauge. A suitable reactor may have two The vessel 70 is provided with a drain line 77 Y 4 350 foot helical coils, such as 70, of 1% inch doubletough Pyrex glass pipe supported on a suitable frame. Chlorine and sulfur dioxide may be injected separately into each coil while the hydrocarbon feed is split and fed into each coil.

The method and apparatus of the present invention is of considerable advantage in that heretofore it Was impractical to carry out photochemical reactions at high pressures without providing expensive equipment, such as glass-lined vessels. In the present invention the disadvantages of the prior art are entirely obviated by providing an elongated, horizontal reaction vessel which has a glass coil constructed, for example, of double-tough Pyrex pipe arranged in the elongated vessel. By immersing the glass reaction tube in a steel vessel which may be designed to withstand pressure as high as 200 to 300 pounds per square inch, it is possible to operate the glass reaction zone at the higher pressures, although the Pyrex glass pipe has a safe-working pressure of only about 50 pounds per square inch gauge. By providing a liquid pool of refrigerant or vaporizable, normally gaseous hydrocarbon in the elongated reaction vessel and confining same therein, it is possible to operate in the glass reaction coil at a pressure in excess of the safe-working pressure of the glass reaction coil. In short, by maintaining a pressure on the exterior of the reaction tube equivalent to the pressure on the interior of the reaction tube, the pressure differential across the reaction tube is balanced and operations may be conducted at high pressures.

In operating the apparatus of the present invention, a reactant mixture, for example, of a paranic type lubricating oil, chlorine, and sulfur dioxide is introduced into a glass or light transparent reaction coil, such as 19, immersed in a reaction vessel, such as 11, in which a body or pool of liquid normal butane is maintained. The lamps, such as 18, are energized to provide light radiations of a suitable wave length which cause a reaction among the several reactants to provide hydrocarbon sulfonyl chlorides which are Withdrawn as the product from coil 19 by line 25. The heat of reaction is removed by vaporization of the normal butane and the vaporized normal butane is condensed on contact with the coil 14 and caused to drop back in the pool which is thus maintained during the operation. Operations may suitably be conducted at a temperature of about 150 F. and a pressure of about pounds which is in excess of the safe-working pressure of coil 19.

It is desirable that the refrigerant or liqueable normally gaseous hydrocarbon have a vapor pressure equal to the pressure at which it is desired to operate. For example, in operations at about F. and 100 pounds per square inch gauge, the steel vessel may be lled with normal butane which will have a vapor pressure of about 100 pounds per square inch at this temperature. The pressure of butane in a steel shell may be from 50 pounds per square inch gauge below to slightly above the reaction pressure inside the glass reaction tube. -Any leakage into the reaction tube may not be detrimental since small amounts of the hydrocarbon refrigerant, such as butane, will not affect adversely the photochemical reaction and may be easily separated from the reactor product.

Another advantage of the present invention is that the hydrocarbon pool or bath of refrigerant serves to remove high heats of reaction from the photochemical reaction and thereby allows maintenance of close control of the reactor temperature. The heat of reaction is removed from the reactor by the vaporized hydrocarbons which is then condensed and this heat is removed from the system by the condensation of the vaporized hydrocarbon. Thus the pool or the liquid hydrocarbon level s maintained above the reaction tubes which are immersed therein.

It is desirable that the lamps be spaced around the glass tubing and spaced away from the outer shell of the steel vessel. Lamps should lalso be placed spaced away from each other in the center of the vessel so that the reaction coil describes a tortuous path through the banks of the lamps.

It is desirable to dry the hydrocarbon or refrigerant in which the bank is immersed in order to eliminate any difficulties by virtue of the electrical connections passing through the pool of refrigerant. The hydrocarbon or refrigerant selected will transmit substantially 100% of the light radiation of photochemical lamps. Butane and the other normally gaseous hydrocarbons possess this requirement.

As pointed out previously, in order to operate eciently, it is desirable that the inner wall of the elongated vessel be coated with a light reecting material, such as stainless steel, aluminum, silver, and the like.

It will be seen from the foregoing description taken with the drawing that we have provided a new and useful reaction vessel and method for operating same in preparing photochemical reactants.

The nature and objects of the present invention having been completely described and illustrated, what we wish to claim as new and useful and to secure by Letters Patent is: l. A reactor Vessel for photochemical reactions which comprises, a vessel adapted to contain a liquid body of a vaporizable refrigerant, a plurality of photochemical lamps arranged in said vessel, a light transparent coil arranged in said vessel to describe a path through said vessel in proximity to said lamps, means connected to the upper part of said vessel for condensing refrigerant, means for introducing reactants into said coil, and means f for withdrawing product from said coil.

2. A reactor vessel for reaction of chlorine and sulfur dioxide with normally liquid hydrocarbons which com- 3. A reactor vessel for reaction of chlorine and sulfurdioxide with normally liquid hydrocarbons which cornprises, an elongated vessel adapted to contain a liquid body of a vaporizable refrigerant, a plurality of spaced apart photochemical lamps arranged longitudinally in said vessel, a glass coil arranged in said vessel to describe a tortuous path through said vessel in proximity to said lamps, means connected to the upper part of said vessel for condensing refrigerant, means for introducing chlorine, sulfur dioxide and normally liquid hydrocarbons into said coil, and means for withdrawing product from said coil.

4. A reactor vessel for reaction of chlorine and sulfur dioxide with normally liquid hydrocarbons which comprises, an elongated vessel adapted to contain a liquid body of a vaporizable hydrocarbon, a plurality of spaced apart longitudinally extending mercury vapor lamps arranged in said vessel, a glass coil arranged in said vessel a vapor space above said body, a plurality of spaced apart mercury vapor lamps arranged in said vessel, a glass coil arranged in said Vessel in proximity to said lamps to describe a tortuous path through said bank, means in said vapor space for condensing refrigerant, means for introducing chlorine, sulfur dioxide and normally liquid hydrocarbons into said coil, and means for withdrawing product from said coil.

6. A reactor vessel for reaction of chlorine and sulfur dioxide with normally liquid hydrocarbons which comprises, an elongated metallic vessel, a liquid body of a vaporizable hydrocarbon refrigerant in said vessel, a plurality of spaced apart mercury vapor lamps arranged longitudinally in said vessel, a glass coil arranged in said vessel in proximity to said lamps to describe a tortuous path through said body, means connected to the upper part of said vessel for condensing refrigerant, means for introducing chlorine, sulfur dioxide and normally liquid hydrocarbons into said coil, and means for withdrawing product from said coil.

7. A vessel in accordance with claim 6 in which the condensing means is a coil provided with means for circulating coolant therethrough arranged in a Vapor space in said vessel.

8. A vessel in accordance with claim 6 in which the vaporizable hydrocarbon refrigerant is dried butane.

9. A reactor vessel in accordance with claim 6 in which the inner wall of the metallic vessel is provided with a reflector surface.

10. A vessel in accordance with claim 6 in which the condensing means is a coil connected to the upper part of said vessel. l

11. A reactor vessel for photochemical reactions which comprises a vessel adapted to contain a liquid body of a vaporizable refrigerant, a plurality of photochemical lamps arranged in said vessel, a light transparent coil arranged in said vessel to describe a path through said vessel in proximity to said lamps to receive radiation therefrom, means connected to the upper part of said vessel and exterior thereto for condensing refrigerant and returning refrigerant to said vessel, means for introducing reactants in said coil, means for withdrawing product from said coil, and means for introducing said liquid body of refrigerant to said vessel.

References Cited in the le of this patent UNITED STATES PATENTS 681,274 Stanley Aug. 27, 1901 2,622,205 Miller et al Dec. 16, 1952 2,656,313 Miller et al. Oct. 20, 1953 2,683,688 Tramm July 13, 1954 2,753,300 Montell July 3, 1956 

1. A REACTOR VESSEL FOR PHOTOCHEMICAL REACTIONS WHICH COMPRISES, A VESSEL ADAPTED TO CONTAIN A LIQUID BODY OF A VAPORIZABLE REFRIGERANT, A PLURALITY OF PHOTOCHEMICAL LAMPS ARRANGED IN SAID VESSEL, A LIGHT TRANSPARENT COIL ARRANGED IN SAID VESSEL TO DESCRIBE A PATH THROUGH SAID VESSEL IN PROXIMITY TO SAID LAMPS, MEANS CONNECTED TO 